|
Light detection and ranging (lidar) have been valuable tools in remote sensing of aerosols near the ground. For the operation of a lidar system, the laser, as a transmitter, plays a vital role in the whole system. Laser Diodes (LD) and Diode-Pumped Solid State (DPSS) laser technology have evolved, making the lidar system more compact compared to Nd:YAG laser sources. However, the lidar system’s long time and continual operation need maintenance to keep the laser source output stable. Also, the laser source is vulnerable to static electricity and needs to stabilize electric power. In this work, a multiwavelength lidar system with a Light Emitting Diode (LED)-based light source is designed and developed to monitor aerosol distribution in the near-ground atmosphere during continuous observation. The LED light source does not require any heat dissipation system and can emit light for long periods with constant output. The LED lamp light sources with wavelengths of 365, 450, 525, and 630 nm (peak power of up to 2W) are used as lidar transmitters. This lidar system visualizes rapid activities of aerosols in the near-range measurement due to its repetition frequency of over 250 kHz. Analysis of the backscattering light intensity with four wavelengths from this LED lidar system produces real time extinction coefficient and size distribution in the near-ground atmosphere. This report discusses the design and practical test of the multi-wavelength LED Lidar.
|
